Barium chloride is an inorganic compound with the formula BaCl2. It is one of the most common water-soluble salts of barium. Like most other water-soluble barium salts, it is a white powder, highly toxic, and imparts a yellow-green coloration to a flame. It is also hygroscopic, converting to the dihydrate BaCl2·2H2O, which are colourless crystals with a bitter salty taste. It has limited use in the laboratory and industry.Barium chloride dihydrate has several applications across various industries. It’s primarily used in the purification of brine solutions in caustic chlorine plants, as a reagent in chemical labs, and for producing other barium compounds. Additionally, it’s found in the production of heat treatment salts, case hardening of steel, pigments, and some lubricating oil additives. It also serves as a component in fireworks, providing a green color, and in some water treatment processes.